High efficiency polymeric sterilant container assembly

Abstract

The present invention relates to a method for sterilizing an article inside a sealed container by placing a polyoxymethylene melt formable co-polymer that has been irradiated between about 1 and 200 kGy and then heated at from about 20° C. to about 90° C. for a selected period of time.

1 . A container of a selected volume on the inside, suitable for low heat sterilizing a selected article positioned in the inside of the container comprising a container insert on the inside of the container comprising a melt formable polyoxymethylene or co-polymer of polyoxymethylene that has been melt formed into a container insert and has been irradiated sufficient to cause chain cleavage without depolymerization or brittleness of the insert such that formaldehyde is released upon subsequent application of low heat to the insert. 
     
     
         2 . The container according to  claim 1  wherein the thickness of the insert is no more than 20 mm. 
     
     
         3 . The container according to  claim 2  wherein the insert is a high surface area fiber or a non-woven mat. 
     
     
         4 . The container according to  claim 1  wherein the polyoxymethylene polymer contains ethylene oxide copolymerized to a suitable level for melt blowing into fibers or non-woven mats. 
     
     
         5 . The container according to  claim 1  wherein the melt forming process is melt blowing. 
     
     
         6 . The container according to  claim 1  wherein the insert is melt formed by spin bonding. 
     
     
         7 . The container according to  claim 1  wherein the radiation dosage is in a range of from about 1 to 200 kGy. 
     
     
         8 . The container according to  claim 1  wherein the insert is part of or attached to the inside of the container. 
     
     
         9 . The container according to  claim 1  wherein the insert is heated in a atmosphere of about 5 to 100 percent relative humidity. 
     
     
         10 . The container according to  claim 1  wherein the insert is one component of a multi component insert. 
     
     
         11 . The container according to  claim 1  wherein the insert further comprises a thermochromic material. 
     
     
         12 . The container according to  claim 1  wherein the container insert is of sufficient weight and surface area that upon low heating the insert the insert releases enough formaldehyde to reach a concentration of at least about 0.1 mg/L in the selected volume. 
     
     
         13 . The container according to  claim 1  wherein the bag is an essentially flat bag having a selected length and width. 
     
     
         14 . The container according to  claim 13  wherein the insert is a non-woven mat having a mat length and width and wherein the mat length and width is selected such that the mat fits in the bag and is of a size at least about half the product of the length times the bag width. 
     
     
         15 . A process for producing a container of a selected volume on the inside suitable for low heat sterilizing a selected article positioned on the inside of the container comprising positioning in the inside of the container, a container insert comprising a melt formable polyoxymethylene or co-polymer which has been melt formed into a container insert and has been irradiated sufficient to cause chain cleavage without depolymerization or brittleness such that formaldehyde is released upon subsequent application of low heat to the insert. 
     
     
         16 . The process according to  claim 15  wherein the insert is melt formed into a high surface area fiber or non-woven mat. 
     
     
         17 . The process according to  claim 15  wherein the container insert is of sufficient weight and surface area that upon low heating the container the insert releases enough formaldehyde to reach a concentration of at least about 0.1 mg/L in the selected volume. 
     
     
         18 . A method of sterilizing an article at low heat in a container of a selected volume on the inside comprising:
 a) positioning the article in the container;   b) positioning a container insert in the container which comprises a melt formable polyoxymethylene or polyoxymethylene co-polymer which has been melt formed into a container insert and has been irradiated sufficient to cause chain cleavage without depolymerization or brittleness such that formaldehyde is released upon subsequent heating of the insert; and   c) heating the insert to a temperature of about 20° C. to about 90° C. for a time sufficient to release formaldehyde and sterilize the article.   
     
     
         19 . The method according to  claim 18  wherein the heating of the insert is accomplished by a method selected from the group consisting essentially of:
 a) heating the container with the insert inside; 
 b) heating the insert and placing it in the container; 
 c) heating the container with external or internal heating pads; 
 d) heating the insert with heating wires placed in or on the insert; and 
 e) heating the container with an externally placed heating element. 
 
     
     
         20 . The method according to  claim 18  wherein the formaldehyde is sustained release at ambient temperature.